Former team boss Walker (left) took the position during the 2013 season, focusing on several areas of IndyCar racing including the introduction of manufacturer aero kits for the 2015 campaign.

“I have appreciated the opportunity to work closely with the team owners, drivers and the team at IndyCar,” said Walker, who also worked on helping set up new events, investment in race control technology and safety improvements on the current cars.

“After two and a half racing seasons, I believe the timing is right to move on to other opportunities.”

Walker will leave his role at the end of August, following the finish of the 2015 season.

Mark Miles, CEO of series parent Hulman & Company, thanked him for his time with IndyCar.

“We have benefited from Derrick’s extensive racing experience, his tireless effort and his passion for IndyCar, and he will be missed,” said Miles.

“We appreciate the thoughtful way Derrick has planned his transition and wish him well in his future endeavours.”